Re: [Qemu-devel] [PATCH 3/4] hw/registerfields: add 64-bit extract/deposit macros

[francisco iglesias]

On 13 December 2017 at 06:17, Philippe Mathieu-Daudé <address@hidden>
wrote:

> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
> ---
>  include/hw/registerfields.h | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/include/hw/registerfields.h b/include/hw/registerfields.h
> index ad9d7a82a3..f59e7f47bd 100644
> --- a/include/hw/registerfields.h
> +++ b/include/hw/registerfields.h
> @@ -35,6 +35,9 @@
>  #define FIELD_EX32(storage, reg, field)
>  \
>      extract32((storage), R_ ## reg ## _ ## field ## _SHIFT,
>  \
>                R_ ## reg ## _ ## field ## _LENGTH)
> +#define FIELD_EX64(storage, reg, field)
>  \
> +    extract64((storage), R_ ## reg ## _ ## field ## _SHIFT,
>  \
> +              R_ ## reg ## _ ## field ## _LENGTH)
>
>  /* Extract a field from an array of registers */
>  #define ARRAY_FIELD_EX32(regs, reg, field)
> \
> @@ -52,6 +55,14 @@
>      d = deposit32((storage), R_ ## reg ## _ ## field ## _SHIFT,
>  \
>                    R_ ## reg ## _ ## field ## _LENGTH, v.v);
>  \
>      d; })
> +#define FIELD_DP64(storage, reg, field, val) ({
>  \
> +    struct {
> \
> +        unsigned int v:R_ ## reg ## _ ## field ## _LENGTH;
> \
>

Hi Phiilppe,

I'm just wondering if 'v' above maybe should be uint64_t? The size of
unsigned int seems to be 'implementation defined' but I would guess 32 bits
is not unsual. Basically wouldn't a field length > 32 above be problematic?

Best regards,
Francisco


> +    } v = { .v = val };
>  \
> +    uint64_t d;
>  \
> +    d = deposit64((storage), R_ ## reg ## _ ## field ## _SHIFT,
>  \
> +                  R_ ## reg ## _ ## field ## _LENGTH, v.v);
>  \
> +    d; })
>
>  /* Deposit a field to array of registers.  */
>  #define ARRAY_FIELD_DP32(regs, reg, field, val)
>  \
> --
> 2.15.1
>
>
>